During operation textile carding machines generate considerable amounts of dust, fibers, and lint which are emitted at various points on the card as the stock proceeds through the machine. Various lickerin and doffer plenums are known in the prior art which are mounted on the upper portions of the machine and connected to suction ducts leading to filtration systems, and are generally adequate to capture most of the dust and fibers emitted upwardly from the upper portions of the card machine.
However, cleaning of the under card chamber or cavity has been a more difficult task to perform due to the size thereof and the turbulence therein generated by the rotation of the elements thereabove. Efforts have been made to eliminate dust and lint in such an area which began with manual, periodic shoveling or scraping of the lint from beneath the machine by workers. Subsequently plenums with suction ducts attached thereto have been installed under the carding elements to capture lint, dust and fly that falls through. Examples of such prior art devices include the British patent to David Walsh British Pat. No. 562,740 in which an under card cleaning system is provided with a collection tube or suction opening at one end and a fan at the other end of the area beneath the carding machine which blows air currents toward the suction tube. A plurality of curved baffles extend from an upper point and curve downwardly toward the suction inlet which are both intended to prevent an upward flow of the air to the rotating parts while enabling air passing along the baffles to convey fly deposited thereon toward the suction opening.
Also, U.S. Pat. No. 2,964,804 to Schonenberger and U.S. Pat. No. 4,057,887 to Gunter are both illustrative of suction plenums which are designed to maintain the underneath area of the carding machine clean from lint, dust and fly.